INSKEEP: So this is something important for attorney general to observe - too many people in prison, he thinks. But what does the Justice Department propose to do about that, given that 200,000 of the people in prison are in federal prison?

JOHNSON: So that costs a lot of money, Steve. The latest numbers we have from 2010 indicate more than $80 billion spent on incarceration in this country.

INSKEEP: OK.

JOHNSON: Attorney General Holder said last month that the feds will no longer seek these mandatory minimum sentences for low-level drug crimes, especially in cases where people have no ties to big trafficking organizations or aren't selling drugs to kids.

Yesterday though, Steve, he said that policy will apply not just to new cases, but to also to cases already in the system; cases where people have not yet been convicted. Which means new cases prosecutors bring every day and cases where somebody may have pleaded guilty but not yet been sentenced...

INSKEEP: Might have been in an arrest from two years ago or something, and then go back and fix it in some way.

JOHNSON: Yeah, absolutely. And prosecutors now have the authority on their own to go back and fix that. But Holder didn't just make a financial argument yesterday. He also made a moral argument against those kinds of inflexible sentences that take a big toll on communities. Let's take a listen.

HOLDER: Because they oftentimes generate unfairly long sentences, they breed disrespect for the system. Used inappropriately they can be counterproductive. And they've had an unmistakable destabilizing effect on particular communities, largely poor and largely of color.

INSKEEP: Oh, now, this is a really interesting thought here, Carrie Johnson. Because you want to have justice but you also need to have a system that is seen as legitimate. And he's saying that the system is undermining its own legitimacy, at least in the eyes of many people who don't like this. But in order to really change this, would he need to get laws changed?

JOHNSON: Yes. That's very important here, Steve. The attorney general and, in many ways, the Obama administration is doing what he can on its own on this problem and others. But Congress needs to weigh in. And importantly, there are a couple of bipartisan bills moving through the Senate right now, in which Tea Party Republicans have partnered with Democrats to dial back sentences in drug cases and other cases, as well.

INSKEEP: Tea Party Republicans and Democrats on the same page.

JOHNSON: Yeah, a very strange bedfellows' coalition but one that really make sense in criminal justice; in part, Because so much money and spent and so much liberty is at stake here. The path is less clear in the House but even some Republicans there are open to this idea. In part, Steve, because red states like Texas, North Carolina and Georgia have already done some of these reforms at the state level.

INSKEEP: Some lawmakers have to be skeptical though of letting criminals out of prison, convicted criminals out of prison more quickly.

JOHNSON: No doubt, not everybody is on board. Earlier this week, Iowa Republican Charles Grassley in the Senate said he wants more mandatory minimum sentences in financial crimes and child porn cases. Going a little bit against the mainstream there. But right now the focus of most of these reforms is on drug crimes. And the biggest prosecutors association in the country or one of them, the National District Attorneys Association, is injecting a note of caution here. They say with violent crime at a record lows, now is not the time to be messing with those strategies that cause such great success.

INSKEEP: It's hard to forecast Congress right now on anything but does it feel like there's a critical mass of support that this is actually something Congress might pass?

JOHNSON: Steve, I've been doing this for a long time. I think now is the best moment we've seen in decades.